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%I #37 Sep 06 2019 02:01:02
%S 0,0,0,0,1,0,2,1,2,1,3,1,3,2,3,3,2,2,3,3,4,3,2,3,3,3,4,4,3,3,3,5,4,5,
%T 4,5,2,4,4,5,4,5,3,5,5,5,2,6,3,6,4,6,3,7,3,6,4,5,3,7,3,5,4,6,2,8,2,6,
%U 5,7,2,8,4,6,7,7,4,9,2,7,4,5,4,9,3,9
%N a(n) = the number of values of m such that the sum of proper unitary divisors of m (A034460) is n.
%C The unitary version of A048138.
%C The offset is 2 as in A048138 since there are infinitely many numbers (all the powers of primes) for which A034460 = 1.
%H Amiram Eldar, <a href="/A324938/b324938.txt">Table of n, a(n) for n = 2..10000</a>
%F a(A063948(n)) = 0.
%e a(8) = 2 since 8 is the sum of the proper unitary divisors of 10 (1 + 2 + 5) and 12 (1 + 3 + 4).
%t us[1] = 0; us[n_] := Times @@ (1 + Power @@@ FactorInteger[n]) - n; m = 100; v = Table[0, {m}]; Do[u = us[k]; If[2 <= u <= m, v[[u]]++], {k, 1, m^2}]; Rest @ v
%Y Cf. A034448, A034460, A048138, A063948.
%K nonn
%O 2,7
%A _Amiram Eldar_, Sep 05 2019
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